Coin testing



D. W. TROY COIN TESTING July 3, 1934.

Filed July 3, 1933 invenor:

Patented iiin'iy 3, i934 I @QEIN TZES'ITWG Daniel W. Troy, Montgomery,Application duly 3, 1933, Serial No. 678,85t l Glaims. (Cl. 194-101) Theinvention relates to the testing, for masystem will operate with avarying current it terial, of coins, tokens, checks, slugs or similarshould be understood that the term alternating devices used to operateor release what are gencurrent is equivalent here to pulsatory orvarying erally known as coin-controlled apparatus, the current, in factto any current with which interm coin as herein used being taken asequiva-' ductive phenomena will arise. f m lent to any such device ofsimilar function. The The preferred system under the method is to objectof the invention is to provide a new. useful, utilize as comparisoncharacteristics of the two efficient, reliable, inexpensive, quick andeasily modified currents the phase displacements due to operated methodfor making material tests of the action of the coins as closed circuitsecm coins, in accordance with their functioning as ondaries linked uponthe magnetic fields. This 65 closed circuit windings upon the magneticfield permits of the balance of amounts of energy of inductive windingscarrying varying or alterwholly unknown heretofore in the art of coinnating current, and to provide similarly cliaractesting and through theuse of apparatus reterized apparatus for carrying the method intosponsive to phase differences makes the auto- 35 effect. These objectsare attained excellently by matic routing of coins easy and certain. 1may, w the ways and means hereinafter described. of course, employdirectly the difference in In the drawing Fig. 1 is an elementaryassemamperage of the currents in the two inductive bly of apparatusarranged to test coins for mawindings, transformer primaries ordinarily,balterial content, Fig. 2 a'detail of the split-phase ancing them whentest coin and standard coin coin-routing device, Fig. 3 a circuitdiagram for function identically, and utilizing their difierence 75 Fig.l, and Fig. 4 a detail showing a variation when these coins fail tomatch in function, and of the system when it is desired to utilizedirectly in such case would operatecoin routing means variations inamperage of the usual pair of curby such agencie as difierentielwindings p rents employed. an electromagnet, or its equivalent. Thephase The primary step of the method consists in displacements, however,are so conveniently $9 linking the coin to be tested upon the magnetichandled, and the indications S0 positive, and the field of an inductivewinding carrying a varyi degree of refinement of comparison so high incurrent and utilizing certain values of the charprafitice that I Prefert0 fl Where 80in acteristics of such current as modified by the shall sy the condition f balance-o1 u l c to action of currents induced withinthe coin to deof the two pha e d p aced curr n s in h termine thedestination of the coin. Preferably ve windingsthis inductive winding isa primary upon the It Should be 1101565 that Hilde! F118 10T%ent core ofa transformer, the coin itself being emmethod the currents afiected byth W 801115, ployed as the'whole secondary winding, complete the testedand standard coin, may be as a g 35 in itself and not a directlyconnected element of as desired; as much as a hundred watts or more 99any other conducting path. of energy may flow in each of the twoinductive The deternunaticn of the destination of the windings. In factthe amount of energy which coin is best effected by employing along withthe may be employed in the test is practically limited coin to betested, linked as described upon the only by the capacity of the coinsto carry induced to held. of an inductive winding, a second and currentswithout undue heating. This immedistandard coin, similarly linked, andbalancing ately lifts the matter of coin testing from the the currentsof the two inductive windings, the comparison of relatively minutecurrent difone against another; the condition of balance ferences to thematching of substantial amounts of characteristics of these two currentsbeing of energy, so that small percentages of difierence,

.' the condition under which the tested coin is acpracticallyinobservable with weak currents, he- 109 cepted and the condition ofunbalance similarly come now considerable absolute quantities, not beingthe condition under which the tested coin only observable with ease butamply strong to is rejected. This is very readily done by employactuateautomatic coin routing mechanism of any ing two transformers, havingappropriate air gaps Actually y a few Watts e y will 50 in their cores,in one of which is permanently be needed in any such automaticmechanism, 3'.

positioned the standard coin and in the other of may, if desired, use ahundred times as much.

which the tested coin may be temporarily intro- Referring to Fig. 1, 1and 2 are two transformer duced duringthe testing process. The currentscores, each having primary windings as at 3 and employed will, ofcourse, generally be alternating *l. The cores of these transformers areprovided and of any desired frequency. However, as the with air gapswide enough to admit a coin chute, no

such as at 5 and-6, the first, that for the standard transformer, beingonly a dummy and long enough, as shown, to contain the standard coin,say a silver quarter dollar, as at 7. On core 1 the transformer windingsare complete with the primary 3 and the secondary which is the coin tobe tested. The standard coin is, of course, connected to nothing andforms in itself the entire secondary winding of its transformer. Thecoin chute 6, leading down from above, say from the top of acoin-controlled mechanism, serves to guide the coin to be tested to aposition as at 8, where it can serve as secondary of the transformer ofwhich 1 is the core, Means are provided for stopping the coin at thispoint, and these may be either automatic as where governed byelectromagnetic means energized by the coin as it enters or descendschute 6, or manually operated as here shown. Here a detent or stop 9 isnormally beneath the coin when at 8 (the dotted circle representing thecoin so at rest) and is arranged to be withdrawn by a lever 10 the endof which may be moved by a would-be purchaser.

The movement of this lever, however, before withdrawing the detent 9first turns on the current through the primaries, by switch 19 and then,before completely withdrawing detent 9, turns off the current, so thatduring a short period of movement of lever 10 the transformers are bothenergized and opportunity given for the comparison of effects upon theirprimary currents to be made. The time required is very short butobviously the apparatus can be arranged to make this interval ample.

Each of the primaries is connected in series with a winding on arelative small electromagnet, see 11 and 12, so positioned that theirfields traverse a metallic disc, say of aluminum, at 13. In Fig. 2 thisdisc is shown in plan with magnets 11 and 12 ,below it. If, now, as andwhen the transformers are functioning, the phase displacements of thetwo primary currents are alike the fields of magnets 11 and 12 will bein phase and there will be no tendency for disc 13 to rotate. On theother hand, should the primary currents have unlike phase displacementthat phase displacement will be manifest in the fields of magnets 11 and12 andthe disc will tend to and actually rotate, to an extent, and sogovern the coin destination, as will be explained. Disc 13 is providedwith two notches, the one at 14 normally permitting a coin in chute 6 todrop freely through, for the disc works in a suitable gating cut in thewalls of this chute. The other notch serves to restore the disc tonormal position after a test has been made. Stops, 15, 15, limit themovement of disc 13. If, therefore, the coins fail to match in effectingmodification of phase displacements in the primary currents, thetransformer action results in a rotary shifting of disc 13 so that thecoin, released by withdrawal of detent, strikes the disc 13 and isrejected sidewise out of the'chute 6 through the side outlet orrejection opening 16. This having been effected the lever, see sectionalview Fig. 2, returning to normal position under influence of a spring orother control as at 17, entering the narrow part of notch 18, returnsdisc 13 to normal position with the chute 6 unobstructed other than bydetent 9 and ready for insertion of another coin. The split-phase meansshown as including the two magnets 11 and 12 and the rotatably mounteddisc 13 are merely typical of any electromagnetic motor mechanismemploying the principle of out-of-phase energization, whether the out ofphase components produce a rotary or progressive magnetic field. Thistype of apparatus, aswell understood, operates through the conditionthat the field of one component, being out of step with that of theother, acts upon currents induced by the other and produces anelectromagnetic drag in this way. The means shown may be considered, asthey are, equivalent to any split-phase motor mechanism adapted to movesuch a detent or coin deflecting means as necessary to rout a coin whichby failing in the test has permitted the two currents to have differentdegrees of phase displacement.

If, however, I prefer to employ the actual dif ferences in amperages ofthe two primary currents I may lead these currents through relatlvelysmall windings, differentially disposed upon a core, and in mannerprecisely similar to that with a differential relay move an armaturewith the difference between these two currents. Such an-armature, ofcourse, will move a coin routing detent. However, as indicated, phasesplit apparatus is preferred and may be operated with a great degree ofsensitiveness, in the sense of close differentiation between coins, withan amount of energy enormously out of proportion to the work to be done.

While the simplest conception of the idea of the invention is to makethe currents within the coins react upon the primary currents it isevident that, should need exist therefor, that the reaction utilizedmight be that in still other windings linked on the fields of theinductive windings actually carrying the energizing currents.

It should be noted that while if phase differences are to be utilizedthe primaries are in shunt relation, if differences in eifects ontertiary windings are to be used the primaries may be in series.

It is obvious that if the detent is withdrawn before and not after acoin is inserted the immediate effect, the transformers being whollyunbalanced in that one has secondary and the other none, is to move disc13 to reject position, so that any coin inserted after movement of leveris rejected. Similarly discs of paper, bakelite, or nonconductingmaterial, dropped down chute 6 immediately produce unbalance of thetransformers and rejection. Iron discs, or washers, unbalancing thetransformers in another way, by increasing the flux, are similarlyrejected, and it is immaterial that such iron members stick, forimmediatelycurrent is turned off they will fall down chute and berejected by disc 13. Naturally the testing will be the same, whether ornot the detent 9 and the switch mechanism and the, return of therejection disc be effected manually or by automatic coin-controlledmeans such as mentioned above. For this reason the means employed areclaimed broadly in their essential aspects.

While described as operative to .selectively receive silver quarterdollars the method, and apparatus when suitably dimensioned, may be usedto selectively receive coins of any kind; the particular coin used asthe standard secondary determining that only a coin of received.

It may be noted here that in, the particular use of the coins, in boththe standard coin and the tested coin the coin becomes to an extent partof the magnetic circuit, the fiux traversing the coin from side to side,as also the entire secondary circuit. The permeability of coins willthus affect their performance as such secthat kind Will be' 1s:- 5 1.The method set ondaries. Both conductivity and permeability of coinsoperate in the testing under my method. Having described my invention,what I claim forth, which consists in linking the coin to be tested as aclosed circuit winding upon the magnetic field of an inductive windingcarrying alternating current and utilizing the difference, if any,between certain characteristics of such current and like characteristicsof another current in a like winding and with a standard coin similarlydestination of the coin being tested, substantially as set forth.

2. The method set forth, which consists in linking the coin to be testedas a closed circuit winding upon the magnetic field of an inductivewinding carrying alternating current and utilizing the difference, ifany, between the phase displacement of such current and the phasedisplacement of another, current in a like winding and with a standardcoin similarly linked to determine the destination of the coin beingtested, substantially asset forth.

3. The method described, which consists in linking the coin to be testedas a closed circuit winding upon the field of a transformer, linking astandard coin in like manner upon the field of another transformer, andutilizing the differences, if any, in the characteristics of respectivecurrents in other windings, one of them linked upon the field of eachtransformer, to automatically determine the destination of the coinbeing tested, substantially as set forth.

4. The method set forth, which consists in matching the action of thecoin to be tested as a closed circuit winding upon the magnetic field ofan inductive winding carrying an alternating current, against the actionof a standard coin similarly functioning upon the magnetic field ofanother inductive winding carrying an alternating current, anddetermining the destination of the coin being tested automatically bythe difference, if any, between said actions, substantially as setforth.

5. The method set forth, which consists in matching the action of thecoin to be tested as a closed circuit winding upon the magnetic field ofan inductive winding carrying an alternatingcurrent, against the actionof a standard coin similarly functioning upon the magnetic field ofanother inductive winding carrying arr-alternating current, anddetermining the destination of the coin by the difference, if any, inphase of to link a coin said alternating currents, substantially as setforth.

6. The method set forth, which consists in displacing the phase of analternating current by the coin to be tested, displacing the phase ofanother alternating current by a standard coin, and utilizing thedifference in phase, if any, between said currents to determine thedestination of the coin being tested, substantially as set forth.

a '7. In apparatus of the class described, the combination with aninductive winding, of a standard coin linked upon the magnetic field ofsuch winding, a second inductive winding, means arranged to betestedupon, the magnetic field of such second inductive winding, and meansarranged to rout coins governed by difference in phase of currents insaid inductive windings, substantially as set forth.

linked to determine the 8. In apparatus of the class described, thecombination with two transformers both arranged to receive coins assecondary windings of such transformers, of coin routing means operatedby phase displaced currents and governed by the difference, if any,between the phases of currents within windings of said transformers,substantially as set forth.

9. In apparatus of the class described; a transformer having a primaryand arranged to receive a coin to betested as its secondary, a secondtransformer having a primary and having a standard coin as itssecondary, and means governed by difference in phase, if any, betweencurrents in said primaries, arranged to rout coins, substantially as setforth.

10. In apparatus of the class described, a transformer having a primaryand arranged to receive a coin to be tested as its secondary, a secondtransformer having a primary and having 'a standard coin as itssecondary, and means governed by differences, if any, in characteristicsof currents in said primaries, arranged to determine the destination ofcoins, substantially as set forth.

11. In apparatus of the class described, a transformer having a wirewound primary and a sec- .ondary composed of a standard coin, a secondtransformer having a wire wound primary and arranged to receive a cointo be tested as its secondary, and automatic means governed bydifferences, if any, in the currents in said primaries arranged todetermine the destination of a coin, substantially as set forth.

12. The method set forth, which consists in producing respectivedisplacements of phase in two alternating currents by a standard coinand a coin to be tested, respectively, and by means of such alternatingcurrents, so modified as to phase, governing the disposition of the cointo be tested in accordance with the difference of phase displacements ofsaid currents, substantially as set forth.

13. The method described, which consists in linking the coin to betested as aclosed circuit winding upon the magnetic field of aninductive 120 winding carrying alternating current and utilizing thedifference, if any, between certain characteristics of such current andlike characteristics of another alternating current in another windingof predetermined inductance to determine the destination of the coin,sustantially as set forth.

14. The method set forth, which consists in linking the coin to betested as a closed circuit winding upon the magnetic field of aninductive winding carrying alternating current and utilizing thedifference, if any, between the phase displacement of such current andthe phase displacement of another current flowing through a winding ofpredetermined inductance to determine the destination of the coin,substantially as. set forth.

15. In apparatus of the class described, a transformer having a primaryand arranged to receive a coin to be tested as its secondary, and astandard inductance of predetermined value, and means governed by thedifference, if any, in the phase displacement of alternating currentsflowing through said primary and said standard inarranged to determinethe DANIEL W. TROY.

